Question 1
Question 2
Ask unlimited questions for free
There are over 65,000 known species of protozoa. About 10,000 species are parasitic.
Medication errors are three times higher among children and infants than with adults.
The ratio of hydrogen atoms to oxygen in water (H2O) is 2:1.
People with high total cholesterol have about two times the risk for heart disease as people with ideal levels.
There are approximately 3 million unintended pregnancies in the United States each year.
For a complete list of videos, visit our video library